Canada's largest city, Toronto, was the epicenter of the biggest SARS outbreak outside of Asia, with almost 250 people sickened and 44 of them dying this year.

(CBS/AP) A World Health Organization virologist has joined the Canadian investigation of a flu-like illness in British Columbia that officials say could be a mild form of SARS or a related virus.

Almost 150 residents and staff members at one nursing home fell ill in recent weeks with sniffles and other symptoms much less severe than the headaches and pneumonia associated with severe acute respiratory syndrome.

Most have completely recovered, but six of the nursing home residents have died of pneumonia-related illness. The latest death, reported Tuesday, was an elderly woman who had typical pneumonia symptoms rather than the distinct pneumonia symptoms of SARS, officials said.

Three of the dead and an unspecified number of others sickened at the Kinsmen Place Lodge in Surrey, a Vancouver suburb, tested positive for coronavirus, the kind associated with SARS, noted Dr. David Patrick, director of epidemiology at the B.C. Center for Disease Control.

If this truly is the SARS coronavirus, "we're definitely uncovering a different pattern of illness than the one described in the spring," Patrick said at a news conference Tuesday. It could be a mutated SARS coronavirus that has lost virulence, he said, a favored hypothesis among many experts.

Dr. Roland Guasparini, chief medical officer for the Fraser Health Authority, said scientists were checking a handful of possible similar cases at a second, unspecified facility.................